Actually your "proof" makes it more likely for xur to be rng. An experiment exists which has to do with what is truly random and what people perceive to be random. The way the experiment is conducted is they take 2 groups of people the first group is assigned to flip a coin 100 time and write each result in order while the second is supposed to come up with a sequence of coin flips that seem random. The results of this test are that the group flipping the coin will almost always have a list that shows 1 or more runs of 5+ in a row, but the second team will almost always peak at a run of three and never go over a run of 5. The result? Very low probability things happen all the time but people have a very difficult time recreating low probability because they feel it is not random.